Some legal experts are saying the assassination of public officials is out of character for the ABT, though, and members themselves are balking at being blamed for the crime, the LA Times reports.

"There is some grumbling among the ABT from sources I have. They feel like they're being blamed for this, that they're being set up," Houston-based criminal justice consultant Terry Pelz told the Times.

The ABT, which isn't part of the larger, California-based Aryan Brotherhood, formed in the 1980s and has a paramilitary structure that stresses obedience and loyalty. The group is known for killing people who try to leave — not murdering civilians or law enforcement.

In fact, attacking senior law enforcement would probably backfire on a prison gang.

"That's going to bring the heat on you," UCLA law professor and gang expert Jorja Leap told the Times. "Long-running gangs on the street are smart enough to know their own limits and don't cross them. The ones that go crazy are the ones that don't survive."

The murder of Kaufman County DA Mike McLelland and his wife, Cynthia, just two months after Assistant DA Mark Hasse was killed has cast a spotlight on the prison gang their office prosecuted, but police are investigating other possible suspects.